code: def left_right_halo_exchange(
      self,
      left_output_halo,
      right_output_halo,
      left_input_halo=None,
      right_input_halo=None,
  ):
      if left_input_halo is None:
          return right_output_halo, left_output_halo
      else:
          left_input_halo.copy_(right_output_halo)
          right_input_halo.copy_(left_output_halo)
  
imports: import torch
  import torch.distributed
  from torch import nn
  import nccl_p2p_cuda
  import peer_memory_cuda
label_desc: Use image node_id 2 for calling the HaloExchangerNoComm obj's underlying member method code with example usage: obj.left_right_halo_exchange(left_output_halo, right_output_halo, left_input_halo, right_input_halo) and returns: right_output_halo,  left_output_halo